Many conventional power tools include triggers or switches that facilitate the transfer of power from a power source to a motor of the tool. For example, power drills have variable speed triggers that transfer a small amount of power to the motor when the trigger is depressed only slightly, but transfer a greater amount of power when fully depressed, thus causing the motor output to increase. These conventional tools may further include a reversing lever or switch that allows the user to reverse the rotational direction of the power tool to, for example, remove a workpiece from a working material. A power source, such as a battery, is coupled to the trigger and the reversing lever to provide appropriate power to the motor, which causes a motor to rotate in a desired direction and speed.
In the conventional tool, the trigger is a variable speed trigger where the amount of power transferred from the power source to the motor depends on how far the trigger is depressed. However, to reverse the direction of the output of the motor, the user must release the trigger and actuate the separate reversing lever located on the tool.
More recent developments in power tools have provided a toggle switch and trigger combination. The combination switch is a simple double-pole-double-throw switch configurable in two positions—forward and reverse. The combination switch supplies power to the motor at only one rotational speed, but can do so in either rotational direction without requiring a separate reversing lever.
Other recent developments have combined a toggle switch with two variable speed triggers so a user can actuate the trigger in a first direction to cause the output of the motor to rotate in a first direction, and can actuate the trigger in a second direction to cause the output of the motor to rotate in a second direction. This design requires two separate triggers that are mechanically coupled together by a rotating toggle switch and are somewhat expensive to manufacture due to the requirement of two switches.